Chuck with quick change

ABSTRACT

A chuck includes a generally cylindrical body and a plurality of jaws reciprocally disposed in the body in communication with a central bore in the body. A first detent extends radially into the central bore and is releasable in a radially outward direction. Upon insertion of an elongated tool shaft having a polygonal cross section into the bore so that a groove in the tool shaft is aligned with the first detent, the first detent engages the groove and axially retains the tool shaft. Upon movement of the jaws so that the jaw faces engage flat sides of the tool shaft, the jaws rotationally retain the tool shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a continuation of, and claims priorityto, U.S. patent application Ser. No. 09/852,936, filed May 10, 2001,which claims priority U.S. Provisional Patent Application Serial No.60/203,713, filed May 12, 2000, which are incorporated by referenceherein.

BACKGROUND OF THE INVENTION

[0002] The present invention relates generally to chucks for use withdrills or with electric or pneumatic power drivers. More particularly,the present invention relates to a chuck of the keyless type which maybe tightened or loosened by hand or by actuation of the driver motor.

[0003] Both hand and electric or pneumatic tool drivers are well known.Although twist drills are the most common tools used with such drivers,the tools may also comprise screw drivers, nut drivers, burrs, mountedgrinding stones, and other cutting or abrading tools. Since the toolsmay have shanks of varying diameter or may have a polygonal crosssection, the device is usually provided with a chuck that is adjustableover a relatively wide range. The chuck may be attached to the driver bya threaded or tapered bore.

[0004] A wide variety of chucks have been developed in the art. In oneform of chuck, three jaws spaced circumferentially approximately 120°apart from each other are constrained by angularly disposed passagewaysin a body attached to the drive shaft. The chuck is configured so thatrotation of the body in one direction with respect to a constrained nutforces the jaws into or away from the gripping relationship with a toolshank. Such a chuck may be keyless if it can be tightened or loosened bymanual rotation. Examples of such chucks are disclosed in U.S. Pat. Nos.5,125,673 and 5,193,824, commonly assigned to the present assignee andthe entire disclosures of which are incorporated by reference herein.Various configurations of keyless chucks are known in the art and aredesirable for variety of applications.

[0005] Various quick change chuck devices are known in the art. Oneexemplary such device includes a body with a central bore that receivesa bit having a polygonal cross section. The body includes a grooveextending transversely across the body and opening into the axial bore.The bit includes an annular groove at its rear end. A wire is disposedin the body groove so that when the bit is pushed into the bore, the bitpushes the wire radially outward. The wire is, however, biased radiallyinward. Thus, when the groove at the bit's rear end aligns with thewire, the wire moves into the bit groove to positively retain the bit inthe chuck bore.

[0006] The chuck body includes a stem portion extending from its rear.The stem may be received in the bore of a three-jawed oblique chuck asdescribed above so that the quick-change chuck is secured to the drillby the three-jawed chuck. Another quick-change device is disclosed inU.S. Pat. No. 5,947,484, the disclosure of which is incorporated byreference herein.

SUMMARY OF THE INVENTION

[0007] The present invention recognizes and addresses the foregoingconsiderations, and others, of prior art constructions and methods.

[0008] Accordingly, it is an object of the present invention to providean improved chuck.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] A full and enabling disclosure of the present invention,including the best mode thereof, to one of ordinary skill in the art, isset forth more particularly in the remainder of the specification,including reference to the accompanying figures, in which:

[0010]FIG. 1 is front plan view, partly in section, of a chuck inaccordance with an embodiment of the present invention;

[0011]FIG. 2 is an exploded view of the chuck as in FIG. 1;

[0012]FIG. 3 is a partial sectional view of a chuck in accordance withan embodiment of the present invention;

[0013]FIG. 4 is a partial sectional view of a chuck in accordance withan embodiment of the present invention;

[0014]FIG. 5 is a partial perspective view of a jaw for use in a chuckin accordance with an embodiment of the present invention engaging abit;

[0015]FIG. 6 is a partial sectional view of a chuck in accordance withan embodiment of the present invention;

[0016]FIG. 7 is a plan view, in section, of a chuck in accordance withan embodiment of the present invention;

[0017]FIG. 8 is a partial sectional view of the chuck as in FIG. 7; and

[0018]FIG. 9 is a partial sectional view of a chuck in accordance withan embodiment of the present invention.

[0019] Repeat use of reference characters in the present specificationand drawings is intended to represent same or analogous features orelements of the invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0020] Reference will now be made in detail to presently preferredembodiments of the invention, one or more examples of which areillustrated in the accompanying drawings. Each example is provided byway of explanation of the invention, not limitation of the invention. Infact, it will be apparent to those skilled in the art that modificationsand variations can be made in the present invention without departingfrom the scope or spirit thereof. For instance, features illustrated ordescribed as part of one embodiment may be used on another embodiment toyield a still further embodiment. Thus, it is intended that the presentinvention cover such modifications and variations as come within thescope of the appended claims and their equivalents.

[0021] Referring generally to FIGS. 1 and 2, a chuck 10 in accordancewith the present invention has a central longitudinal axis depicted bythe dashed line designated at 12. Chuck 10 includes a front sleeve 14, arear sleeve 16, and a plurality of jaws 18. A body 20 is generallycylindrical in shape and comprises a nose or forward section 22 and atail or rearward section 24. An axial bore 26 is formed in the nosesection and is somewhat larger than the largest tool shank that thechuck is designed to accommodate. As should be understood in this art,body 20 may be formed from steel bar stock or any other suitablematerial.

[0022] Body 20 defines a threaded bore 28 in its tail section. Bore 28is of a standard size to mate with the drive shaft of a powered or handdriver (not shown). While a threaded bore 28 is illustrated, such borecould be replaced with a tapered bore of a standard size to mate with atapered drive shaft. The bores 26 and 28 may communicate at a centralregion of body 20. The central region may be formed with a socket toaccept a drive bit so that the body may be screwed onto to the spindleby the bit.

[0023] Body 20 also defines three passageways 32 to respectivelyaccommodate the three jaws 18. In a three-jaw configuration, eachpassageway, and therefore each jaw, is separated from each adjacentpassageway by an arc of approximately 120°. The longitudinal axes ofpassageways 32 and jaws 18 are angled with respect to the chuck'slongitudinal axis 12 but intersect the chuck axis at a common pointahead of chuck body 20. Each jaw has a tool engaging face 34 that isgenerally parallel to axis 12.

[0024] Body 20 includes a thrust ring member 36, which in a preferredembodiment forms an integral part of the body. Although not presentlypreferred, the thrust ring may be a separate component from the body'smain portion. A ledge 40 extending forward from thrust ring 36 receivesa bearing assembly 42. The bearing assembly includes a bearing cage 44enclosing bearing balls 46 that forwardly bear, with respect to chuckbody 20, on a forward washer 48 and rearwardly bear on a rearward washer50. Rearward race 50 abuts a shoulder surface 52 formed between theraised and ledge portions of thrust ring 36. Forward race 48 bears in anaxially forward direction against a spring washer 122 that in turn bearsagainst a shoulder 54 of sleeve 14. Bearing assembly 42 may comprise anysuitable construction, for example a bearing assembly of the typedescribed in U.S. Pat. No. 5,348,318, incorporated by reference herein.

[0025] Tail section 24 of body 20 can include a rear cylindrical portionhaving a knurled surface 56 thereon for receipt of rear sleeve 16. Therear sleeve may be pressed onto the knurled surface, or could beretained in place by press fit without knurling or by use of a key.

[0026] At the front end of the chuck, nose section 22 is beveled and isadapted to receive a nose piece 57 for restraining front sleeve 14 fromforward axial movement with respect to the chuck body. Alternatively, asnap ring or other suitable mechanism may be used to axially restrainthe sleeve. Nose piece 57 may be pressed onto nose section 22 orattached in any other suitable manner. Rearward axial movement of thesleeve on the body is prevented by thrust ring 36 through bearingassembly 42.

[0027] The outer circumferential surface of sleeve 14 may be knurled ormay be provided with longitudinal ribs or other protrusions to enablethe operator to grip it securely. The front and rear sleeves may befabricated from a structural plastic such as polycarbonate, a filledpolypropylene, for example glass filled polypropylene, or a blend ofstructural plastic materials. Other composite materials such as, forexample, graphite filled polymerics could also be suitable in certainenvironments. Further, either sleeve may be constructed from suitablemetals, such as steel. Moreover, as would be appreciated by one skilledin the art, the materials from which the chuck of the present inventionis fabricated will depend on the end use of the chuck, and the above areprovided by way of example only.

[0028] An interior surface 59 of sleeve 14 defines female threads 58.The threads are a modified square thread formation in an eight pitchconfiguration along the length of sleeve 14. It should be understood,however, that any suitable thread shape or formation may be employed,for example including a modified buttress thread. In one preferredembodiment, the squared interface between the outer surface and the backside of thread 58 is replaced by a curved surface.

[0029] A driving disk 60 includes a male thread 62 extending about anouter circumferential surface 64. Thread 62 has the same pitch as thread58 so that when thread 62 is received by thread 58, relative rotationbetween sleeve 14 and driving disk 60 moves the driving disk axiallywithin the sleeve. In particular where the driving disk is molded,thread 62 may have sloped sides, for example at an approximately 5°slope, extending from surface 64 to the thread's outer diameter.

[0030] Driving disk 60 includes three equiangularly spaced apart radialslots 106 extending entirely radially through the disk. Slots 106 arecylindrical in shape and may be formed by boring radially inward intothe driving disk outer surface with a suitable boring tool. Jaw endsections 68 are formed in a cooperating semi-circular shape so that theslots 106 slideably receive the respective jaws. The slots allow the jawends to move radially as the driving disk moves the jaws between openand closed positions. A dry lubricant coating may be provided on the jawends and/or slots 106 to facilitate this movement. The cooperationbetween the jaw ends and slots 106 maintains the jaws at the properangle with respect to the driving disk so that the jaws are maintainedin alignment in the jaw passageways in the assembled chuck.

[0031] Rotation of sleeve 14 clockwise, when viewed from nose section22, moves driving disk 60 axially forward with respect to the chuckaxis, thereby moving jaws 18 to a closed position. Conversely,counter-clockwise rotation of the front sleeve moves the jaws in anopening direction. A stop 92 is provided at the rear edge of thread 58.When the jaws reach a fully open position, a rear edge 94 of thread 62abuts stop 92. This prevents further rotation of the sleeve with respectto the driving disk. A similar stop (not shown) is provided at the frontend of thread 58 to stop a forward edge 98 of thread 62 to prevent thejaws from binding in the fully closed position when there is no tool inthe chuck bore.

[0032] Thread 62 defines one turn that extends slightly less than 360°around surface 64 of driving disk 60. A gap 100 between edges 94 and 98has an angular width greater than the width of stop 92. This facilitatesthe chuck's assembly in that the driving disk may be placed directlydown onto thread 58 over the stop. Rear sleeve 16 prevents the drivingdisk from disengaging from the sleeve when the chuck is in a fully openposition in which rear thread edge 94 abuts stop 92.

[0033] Bearing assembly 42 may comprise any suitable construction. FIG.2, for example, illustrates two bearing configurations 42 a and 42 b. Inthe embodiment indicated at 42 a, the washer that forms bearing race 48includes radially aligned recesses 114 in the washer's rearward face sothat each of bearing balls 46 are received in a respective recess 114.

[0034] As it is rotated, sleeve 14 exerts a relative rotational forcebetween races 48 and 50. Normally, washer 48 carries balls 46 so thatcage 44 rotates with washer 48. Before the jaws close onto the tool,however, there is relatively little rearward axial force against washer50. Thus, balls 46 slide against the washer, which remains in positionagainst the chuck body. Where the frictional force between balls 46 andwasher 50 is greater than that between sleeve 14 and washer 48 throughspring 122, the entire bearing assembly remains rotationally held to thebody as the sleeve rotates.

[0035] When the jaws close onto a tool shank, driving disk 60 exertsrearward axial force against sleeve 14, which in turns translates thisforce to the body through spring 122 and bearing 42 a. At this point,the increased frictional force between balls 46 and race 50 causes theballs to rotate against the washer, which is rotational held by frictionto thrust ring 36. Since sleeve 14 rotationally drives washer 48 byfriction through spring washer 122, this causes balls 46 to roll out oftheir recesses 114 into the next recess. Continued rotation of sleeve 14continues movement of the balls through successive recesses, causing aclicking sound that notifies the operator that the chuck is approachinga fully tightened position.

[0036] In another embodiment, bearing 42 b includes a first race 48having recesses 114 defined about the radially outward edge of itsrearward face. Opposite race 50 includes a shroud 116 extending axiallyforward therefrom. The shroud defines a plurality of spring arms 118biased axially forward toward washer 48 so that tabs 120 defined at thedistal ends of arms 118 engage respective recesses 114. Thus, as sleeve14 is rotated to a closed position, races 48 and 50 are rotationallylinked to each other and rotate either with sleeve 14 or chuck body 20,depending on whether the sleeve or the body exerts the greaterfrictional force on the bearing assembly. As should be understood bythose skilled in the art, this depends on the dimensions of thecomponents and the materials from which they are made. When the chuckjaws tighten onto a tool shank, however, frictional forces betweenwasher 48 and sleeve 14 through spring washer 122, and between washer 50and thrust ring 36, overcome the link between washer 48 and 50. Furtherrotation of sleeve 14 therefore rotates washer 48 with respect to washer50, overcoming the biasing force of spring arms 118. Thus, the arms aredeflected so that each tab 120 moves out of its recess 114 into the nextrecess. Continued rotation of sleeve 14 moves tabs 120 in and out ofsuccessive recesses, creating a clicking sound notifying the user thatthe chuck is approaching a fully closed position.

[0037] Upon opening the chuck, having either bearing 42 a or 42 b, froma fully closed position, washers 48 and 50 initially rotate with respectto each other, again creating the clicking sound. As soon as the jawsrelease from the tool shank, however, the bearing assembly operates asdescribed above prior to the fully closed position.

[0038] Driving disk 60 includes a blind bore 124 that extends radiallyinward from the driving disk's outer surface 64. A spring 126 biases adetent ball 128 radially outward from bore 124. As sleeve 14 rotatesabout the driving disk, ball 128 rides on lands 130 between the groovesof thread 58. A depression 132 is formed in the lands so that ball 128moves into the depression when the jaws' tool engaging surfaces 34define a predefined diameter. The diameter is slightly less than thecross width of the a tool, preferably a multi-sided tool, which thechuck is to receive. In one preferred embodiment, for example, thediameter is slightly less than one-quarter inch. Ball 128 makes aclicking sound when entering depression 132 and slightly inhibitsrotation of sleeve 14. This notifies the user that the jaws are in thepredetermined position to receive the tool shank.

[0039] When the jaws are in the predetermined position, as located bythe detent comprised of ball 128 and depression 132, a multi-sided bit134 that is pushed into bore 26 against tool engaging surfaces 34 ofjaws 18 pushes the jaws radially outward. This forces the jaws axiallyrearward in jaw passageways 32, thereby pushing driving disk 60 andsleeve 14 axially rearward on body 20 against the force of spring washer122. When the bit is fully inserted into bore 26, spring 122 applies aforward bias to the jaws through sleeve 14 and driving disk 60 to retainthe tool in the bore. The tool's flat sides 125, and their interfaces127, generally prevent the tool's rotation within the bore.

[0040] It should be understood that various other locating mechanismsmay be employed within the present invention. For example, referring tothe embodiment shown partially in FIG. 3, bore 124 opens radially inwardfrom driving disk 60. Depression 132 is located at a predeterminedposition in body tail section 24.

[0041] In a still further embodiment, and referring to FIG. 4, bore 124is located in sleeve 14 and opens radially inward to a groove of thread58. Spring 126 biases a detent ball or pin 133 into the thread atpredetermined position on the thread so that driving disk thread 62(FIG. 2) engages pin 133 at the point where tool engaging jaw surfaces34 (FIG. 2) define the predetermined diameter. Further rotation ofsleeve 14 pushes pin 133 up into bore 124.

[0042] To release the bit in any of these embodiments, an operator pullssleeve 14 axially rearward against the force of spring 122. This pullsdriving disk 60, and therefore jaws 18, axially rearward, therebyreleasing the bit.

[0043] Referring again to FIGS. 1 and 2, the chuck includes a positivelocking mechanism to retain bit 134. For example, each jaw 18 may definea blind bore 136 extending radially inward from its tool engagingsurface 34. A spring 138 biases a detent ball 140 radially inward. Themouth of bore 136 may be peened about its edge to create a lip thatretains ball 140 in the bore. As bit 134 moves into bore 26, the bit'srear edge pushes ball 140 back into bore 136. As a groove 142 at therear end of bit 134 reaches the bore, however, spring 138 pushes ball140 into the groove, thereby positively retaining bit 134 axially inbore 26. To remove the bit, an operator pulls the bit axially forward sothat the rear end of bit 134 pushes ball 140 back into bore 136.

[0044] In another preferred embodiment, and referring to FIG. 5, aforward portion of the tool engaging surface 34 of each jaw 18 may beground so that the tool engaging surface extends forward from a rearheel 144 defined at the rearward edge of the jaw face. The groundforward portion defines the predetermined diameter. As bit 134 is pushedinto bore 26, the bit pushes jaws 18 radially outward so that the bitslides axially rearward along the jaw face. When groove 142 aligns withheel 144, the heel moves into the groove to positively retain the bit.

[0045] In a still further embodiment illustrated in FIG. 6, a bore 146is defined through thrust ring 36. A spring 148 extends between a detentball 150 and a biasing ball 152. Normally, biasing ball 152 is pushedradially inward by a tapered surface 154 of an annular ring 156 attachedto the inner surface of sleeve 14. As bit 134 is inserted into bore 26,the bit pushes ball 150 back into bore 146 until groove 142 aligns withthe bore. At this point, ball 150 moves into groove 142 to positivelyretain the bit. As an operator pulls sleeve 14 rearward against spring122, ring 156 also moves rearward, allowing ball 152 to ride radiallyoutward against tapered surface 154. This partially relieves thepressure against ball 150, allowing the operator to more easily removebit 134 from bore 26.

[0046] Accordingly, an operator may secure a tool, for example a bithaving a circular cross-section, in chuck 10 by rotation of sleeve 14 toclamp jaws 18 onto the tool shank. Alternatively, the operator mayrotate the sleeve until it reaches the predetermined position asindicated by the locator mechanism and thereafter insert and extracttools of a predetermined size against the biasing force provided byspring 122. This mode of operation is particularly suited to tool shankshaving a polygonal cross-section. Thus, the chuck may be operated in asleeve-tightening manner or in a quick-change manner.

[0047] Furthermore, it should be understood that the present inventionmay be employed in conjunction with various chuck configurations. Forexample, referring to FIGS. 7 and 8, chuck 10 includes a body 20, a nut158, a nosepiece 57 and a plurality of jaws 18. Body 20 is generallycylindrical in shape and comprises a nose or forward section 22 and atail or rearward section 24. The nose section defines an axial bore 26that is somewhat larger than the largest tool shank that the chuck isdesigned to accommodate. A threaded bore 28 is formed in tail section 24and is of a standard size to mate with the drive shaft of a powered orhand driver (not shown). The bores 26 and 28 may communicate at acentral region of body 20. While a threaded bore 28 is illustrated, suchbore could be replaced with a tapered bore of a standard size to matewith a tapered driveshaft.

[0048] Body 20 defines three passageways 32 to accommodate the threejaws 18. Each jaw is separated from the adjacent jaw by an arc ofapproximately 120°. The axes of passageways 32 and jaws 18 are angledwith respect to the chuck center axis such that each passageway axistravels through axial bore 26 and intersects the chuck axis at a commonpoint ahead of the chuck body. The jaws form a grip that moves radiallytoward and away from the chuck axes to grip a tool, and each jaw 18 hasa tool engaging face generally parallel to the chuck body axis. Threads160, formed on each jaw's opposite or outer surface, may be constructedin any suitable type and pitch.

[0049] Body 20 includes a thrust ring 36 that includes a plurality ofjaw guideways 162 formed around its circumference to permit retractionof the jaws therethrough and also includes a ledge portion to receive abearing assembly 42.

[0050] Body tail section 24 includes a knurled surface that receives anoptional rear sleeve 16 in a press fit. It should be understood,however, that the chuck, as well as the chucks described above, may beconstructed with a single sleeve having no rear sleeve.

[0051] Chuck 10 includes a driving disk formed as a one piece nut 158having threads 164 for mating with jaw threads 162. Nut 158 ispositioned about the body in engagement with the jaw threads so thatwhen the nut is rotated with respect to body 20, the jaws will beadvanced or retracted depending on the nut's rotational direction.

[0052] The nut's forward axial face includes a plurality of recessesthat receive corresponding drive dogs extending from the inner surfaceof front sleeve 14. Accordingly, sleeve 14 rotationally drives nut 158.Nosepiece 57 retains sleeve 14 against forward axial movement. Nosepiece57 may be coated with a non-ferrous metallic coding to prevent rust andto enhance its appearance.

[0053] The outer circumferential surface of front sleeve 14 may beknurled or may be provided with longitudinal ribs or other protrusionsto enable the operator to grip it securely. In like manner, thecircumferential surface of rear sleeve 16, if employed, may be knurledor ribbed if desired.

[0054] A retainer 166 press fit to body 20 retains nut 158 in theaxially forward direction. Retainer 166 includes a frustoconical section168 that facilitates movement of jaws 18.

[0055] In operation, an operator may close the chuck onto a tool shankby rotation of sleeve 14 so that jaws 18 move in passageways 32 to closeupon the tool. Rotation of the sleeve in the opposite direction retractsthe jaws from the tool, allowing the tool's removal from bore 26.Alternatively, the sleeve may be rotated so that the jaws are moved backto their fully retracted position as shown in FIG. 7, and a bit 134 maybe retained in bore 26 by a quick-change mechanism including a spring170 and detent ball 172 located within a bore 174 extending radiallythrough body 20. Spring 170 extends between retainer 166 and ball 172 sothat the spring biases the ball radially inward toward bore 26. Ball 172is retained in bore 174 by a lip at the radially inward mouth of bore174 that is formed, for example, in the drilling process or by peeningthe bore mouth. The diameter of the lip is such that a portion of ball172 extends into bore 26 when spring 170 pushes the ball against thelip.

[0056] As an operator inserts bit 134 into bore 26, the bit's rear endpushes ball 172 back into bore 174 until an annular groove 142 at thebit's rear end aligns with the bore. At this point, spring 170 pushesball 172 into groove 142 to positively retain bit 134 in the axialdirection. In the fully open position, tool engaging surfaces 34 of jaws18 define a predetermined diameter approximately equal to the width ofbit 134. Thus, tool engaging surfaces 34 engage flat sides 176 of bit134, thereby preventing its rotation.

[0057] In a still further embodiment illustrated in FIG. 9, one or morespring washers 122 are disposed between nosepiece 57 and front sleeve 14so that the sleeve is axially reciprocal with respect to the body. Thenut recesses and corresponding sleeve drive dogs permit the sleeve tomove with respect to the nut as well. Bore 174 receives a detent ball172 and a pin 178 that extends radially outward from bore 174 through ahole in retainer 166 so that an end of pin 178 abuts the inner surfaceof sleeve 14.

[0058] In the normal position of sleeve 14 shown in FIG. 9, the distalend of pin 178 abuts sleeve 14 at the radially inward edge of a taperedsurface 180 so that the pin forces ball 172 into chuck bore 26. Toinsert a bit 134 (FIG. 7), an operator pushes sleeve 14 axially forwardagainst the force of springs 122 so that tapered surface 180 aligns withthe distal end of pin 178. As the operator then pushes the bit into bore26, the bit's rear end pushes ball 172 back into bore 174 so that thedistal end of pin 178 rides up tapered surface 180. When the bit isreceived in bore 26 such that the bit's annular groove 142 (FIG. 7) isaligned with bore 174, the operator releases sleeve 14. Springs 122 pushthe sleeve back to its position shown in FIG. 9 so that tapered surface180 pushes pin 178 radially inward through bore 174 so that bit annulargroove 142 (FIG. 7) receives ball 172 to axially retain the bit in bore26.

[0059] While one or more preferred embodiments of the invention havebeen described above, it should be understood that any and allequivalent realizations of the present invention are included within thescope and spirit thereof. The embodiments depicted are presented by wayof example only and are not intended as limitations upon the presentinvention. Thus, it should be understood by those of ordinary skill inthis art that the present invention is not limited to these embodimentssince modifications can be made. Therefore, it is contemplated that anyand all such embodiments are included in the present invention as mayfall within the scope and spirit thereof.

In the claims:
 1. A chuck for use with a manual or powered driver havinga rotatable drive shaft and an elongated tool shaft having a polygonalcross section and defining a circumferential groove, said chuckcomprising: a. a generally cylindrical body having a nose section and atail section, said tail section being rotatable with said drive shaft ofsaid driver and said nose section having a central bore formed therein;b. a grip mounted in said body in communication with said axial bore;and c. a first detent located in said grip and extending radially intosaid bore, said first detent being releasable in a radially outwarddirection relative to said grip; wherein, upon movement of said grip toa predetermined position, the tool shaft may be inserted so that saidgrip engages the polygonal surfaces of the tool to rotationally retainthe tool, and wherein said detent releasably engages the groove formedin the tool shank.
 2. The chuck as in claim 1, wherein said gripincludes a plurality of jaws.
 3. The chuck as in claim 2, wherein saidbody nose section includes a plurality of angularly disposed passagewaysformed therethrough and intersecting said axial bore, and wherein eachsaid passageway slidably receives a separate one of said jaws.
 4. Thechuck as in claim 2, including a second detent operatively disposedbetween said jaws and said body, and including a catch, said seconddetent and said catch being disposed with respect to each other so thatsaid second detent engages said catch when said jaws are at saidpredetermined position at which said jaws engage the polygonal surfacesof the tool shaft when the tool shaft is inserted into said centralbore.
 5. A chuck for use with a manual or powered driver having arotatable drive shaft and an elongated tool shaft having a polygonalcross section and defining a circumferential groove, said chuckcomprising: a. a generally cylindrical body having a nose section and atail section, said tail section being rotatable with said drive shaft ofsaid driver and said nose section having a central bore formed therein;b. a generally cylindrical sleeve disposed rotatably about said body; c.a grip mounted in said body in communication with said axial bore; d. anut disposed about said body in axially driving engagement with saidgrip and rotatable with respect to one of said sleeve and said body sothat relative rotation between said nut and said one of said sleeve andsaid body axially drives said grip; and e. a first detent extendingradially into said bore, said first detent being releasable in aradially outward direction; wherein, upon movement of said grip to afirst position, insertion of the tool shaft into said bore so that saidgroove is aligned with said first detent, said first detent engages saidgroove and axially retains said tool shaft, and wherein said griprotationally retains the tool shaft by engaging the polygonal sides ofthe tool shaft.
 6. The chuck as in claim 5, wherein said grip includes aplurality of jaws.
 7. The chuck as in claim 6, wherein said body nosesection includes a plurality of angularly disposed passageways formedtherethrough and intersecting said axial bore, and wherein each saidpassageway slidably receives a separate one of said jaws.
 8. The chuckas in claim 7, wherein said at least one jaw defines a bore extendingradially into said jaw from said jaw face, wherein said jaw bore definesa restricted opening at said jaw face, wherein said first detentincludes a ball disposed in said jaw bore and a spring disposed in saidjaw bore so that said spring biases said ball toward said restrictedopening, and wherein the diameter of said ball is greater than the widthof said restricted opening so that said ball extends outward of said jawface when said ball engages said restricted opening.
 9. The chuck as inclaim 7, wherein said first detent is defined in said body.
 10. Thechuck as in claim 9, wherein said body defines a bore extending radiallyinto said body from said central bore, wherein said radial bore definesa restricted opening at said central bore, wherein said first detentincludes a first ball disposed in said radial bore and a spring disposedin said radial bore so that said spring biases said first ball towardsaid restricted opening, and wherein the diameter of said first ball isgreater than the width of said restricted opening so that said firstball extends radially into said central bore when said first ballengages said restricted opening.
 11. The chuck as in claim 10, whereinsaid radial bore extends through said body to an outer circumference ofsaid body, wherein said detent includes a second ball disposed in saidradial bore so that said spring is disposed between said first ball andsaid second ball, and wherein said second ball extends radially outwardof said circumferential surface and engages an inner circumferentialsurface of said sleeve.
 12. The chuck as in claim 11, wherein said innercircumferential surface defines a cam and wherein said sleeve is axiallymovably disposed on said body so that movement of said sleeve moves saidcam against said second ball and thereby increases or releases pressureon said first ball through said spring, depending on the direction ofsaid movement.
 13. The chuck as in claim 7, including a second detentdisposed in one of said nut and said sleeve and a catch in the other ofsaid sleeve and said nut, said second detent and said catch beingdisposed with respect to each other so that said second detent engagessaid catch when said jaws are at said first position at which said jawsengage said flat sides of said tool shaft when said tool shaft isinserted into said central bore.
 14. The chuck as in claim 13, whereinsaid catch is a depression defined in said other of said sleeve and saidnut.
 15. A chuck for use with a manual or powered driver having arotatable drive shaft, said chuck comprising: a generally cylindricalbody having a nose section and a tail section, said tail section beingrotatable with said drive shaft of said driver and said nose sectionhaving a central bore formed therein; a. a plurality of jawsreciprocally disposed in said body in communication with said centralbore, each of said jaws having a jaw face formed on one side thereof; b.a first detent formed in at least one of said plurality of jaws and saidbody and extending radially into said bore, said first detent beingreleasable in a radial direction with respect to said at least one ofsaid plurality of jaws and said body; and c. an elongated tool shafthaving a polygonal cross section and defining a circumferential groove,wherein, upon insertion of said tool shaft into said bore so that saidgroove is aligned with said first detent, said first detent engages saidgroove and axially retains said tool shaft, and wherein, upon movementof said jaws so that said jaw faces engage flat sides of said toolshaft, said jaws rotationally retain said tool shaft.
 16. The chuck asin claim 16, including a driver in axial driving engagement with saidjaws.
 17. The chuck as in claim 15, wherein said first detent is definedin at least one of said jaws.
 18. The chuck as in claim 17, including asecond detent operatively disposed between said jaws and said body, andincluding a catch, said second detent and said catch being disposed withrespect to each other so that said second detent engages said catch whensaid jaws are at a predetermined position at which said jaws engage saidflat sides of said tool shaft when said tool shaft is inserted into saidcentral bore.
 19. A chuck for use with a manual or powered driver havinga rotatable drive shaft, said chuck comprising: a. a generallycylindrical body having a nose section and a tail section, said tailsection being rotatable with said drive shaft of said driver and saidnose section having a central bore formed therein and a plurality ofangularly disposed passageways formed therethrough and intersecting saidaxial bore; b. a generally cylindrical sleeve disposed rotatably aboutsaid body; c. a plurality of jaws slidably positioned in each of saidangularly disposed passageways, each of said jaws having a jaw faceformed on one side thereof; d. a nut disposed about said body in axiallydriving engagement with said jaws and rotatably with respect to one ofsaid sleeve and said body so that relative rotation between said nut andsaid one of said sleeve and said body axially drives said jaws in saidpassageways; e. a first detent extending radially into said bore, saidfirst detent being releasable in a radially outward direction relativeto said jaws; f. an elongated tool shaft having a polygonal crosssection and defining a circumferential groove; g. a spring disposedoperatively between said body and said jaws so that said spring biasessaid jaws axially forward in said passageways; h. a second detentoperatively disposed between said jaws and said body; and i. a catch,said second detent and said catch being disposed with respect to eachother so that said second detent engages said catch when said jaws areat a predetermined position at which said jaws engage said flat sides ofsaid tool shaft when said tool shaft is inserted into said central bore,wherein, upon insertion of said tool shaft into said bore so that saidgroove is aligned with said first detent, said first detent engages saidgroove and axially retains said tool shaft, and wherein, upon movementof said jaws axially in said passageways to said first position, saidjaws rotationally retain said tool shaft.
 20. The chuck as in claim 19,wherein said nut includes a driving disk slidably disposed on said bodyand having an external screw thread, and wherein said sleeve defines aninternal screw thread that meshes with said external screw threadwhereby when said sleeve is rotated with respect to said body, said jawsare moved thereby.
 21. The chuck as in claim 20, wherein said seconddetent is disposed in one of said nut and said sleeve and said catch isdisposed in the other of said sleeve and said nut.
 22. The chuck as inclaim 20, wherein said second detent is disposed in one of said nut andsaid body and said catch is disposed in the other of said nut and saidbody.
 23. The chuck as in claim 19, wherein each of said jaws definethreads thereon and wherein said nut defines threads that engage saidthreads of said jaws so that rotation of said nut moves said jawsaxially in said passageways.